• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The roles water in living organisms and water as a habitat for organisms

Extracts from this document...

Introduction

Michael Osgood 2/10/2 The roles water in living organisms and water as a habitat for organisms Introduction Water is the most abundant liquid on the planet. It covers 2/3rds of the earth's surface, and at least 60% of living organisms is water. This value may be as large as 99% - in a jellyfish. The reason for such a large amount of water making up organisms is the fact that it is a major cell constituent - more on that later. Water is a simple molecule yet has many interesting properties which contribute to its importance. Structure Water is made up of two hydrogen atoms bonded to one oxygen atom. They are covalently bonded and the intramolecular covalent bonds are very strong. The structure is non-linear, due to the electron pair repulsion of the two lone pairs of electrons on the oxygen atom. Major cell constituent Often 2/3rds or more of living cells are water. The water is found mainly in the cytoplasm, and it plays a vital role in many functions of the cell: in all organisms - metabolism, and in plants photosynthesis and support. ...read more.

Middle

Cerebro-spinal fluid, amniotic fluid, mucus and pleural fluid (the latter in the lungs). All of these are mainly water, and provide either lubrication or protection and cushion, in different ways. Support The turgidity of plants cells is what keeps them upright, and is down to the fact that the cell exerts a force equal to the force of the water entering the cell by osmosis. This balance of force makes the cell stiff. This turgidity helps to support the leaves and stems of many plants. Reactant Reactions are constantly occurring in an organism, catalyzed by enzymes. Water allows many of these reactions to occur, as often the reactants need to be ionized. Water also plays a major part in gaining energy from the sun, as it is a key part in the reaction by which green plants obtain light energy from the sun and store it as chemical energy: 6H2O + 6CO2 C6H12O6 + 6O2 Monosaccharides (such as alpha glucose) join together to by the process of condensation to form larger molecules of starch. ...read more.

Conclusion

This provides an ideal habitat for marine organisms. When mammals get hot, they sweat. Sweat contains mostly water, and therefore a fairly large amount of energy required to evaporate it - this has a large cooling effect on the body. Plants lose water via transpiration, which helps the uptake of nutrient rich water from the soil, and also prevents the temperature of the plant from rising too high. Habitat Water is an ideal medium for life because: * It provides a protective shield * It prevents the cell from drying out * It provides support and buoyancy to organisms * Its good solvency favours the supply of nutrients to the plants, and the removal of waste products from all organisms. * It allows the oxygen required for respiration to be dissolved in it, and its good mobility means it can get virtually anywhere in an organism. * Fertilization - a surrounding body of water disperses the offspring reducing the risk of competition. * Aquatic organisms have very little need for temperature control mechanisms. * Water filters out harmful UV rays from the sun. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Green Plants as Organisms section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Green Plants as Organisms essays

  1. Marked by a teacher

    The roles water in living organisms and water as a habitat for organisms

    5 star(s)

    Also, gas exchange in the alveoli requires a moist surface, and gas exchange takes place in solution. Transport Both blood and sap are essential for the transportation of food, waste products and many more substances in animals and plants. These two mediums consist of mainly water, and it ensures that

  2. Marked by a teacher

    "The Importance of Water to living Organisms"

    4 star(s)

    This attraction is known as 'hydrogen bonding' (2). Another interesting property is that it has a very high heat capacity, which means that it takes a lot of energy to make water boil and a large amount of energy must be removed to make water freeze. As a result of this water in our cells and on the

  1. Describe and explain the roles of water in living organisms and as an environment ...

    The body would be self-poisoned and die within a week. On average, humans should drink around 2 litres of water a day to keep the cells and the body functioning properly. Water is excreted from the body in 3 main ways: about 600g through breathing, 500g through perspiration and 1,400g through urination/excrement per day.

  2. The Importance Of Water To Living Organisms

    dissolve soluble foods, meaning large starch molecules must be broken down into soluble sugars. Also many organisms living in water spend most of their time underwater, yet they require oxygen to respire, and as water is such a good solvent the required oxygen gas is dissolved in water.

  1. Investigation in to the effect of bile salts on the digestion of fat.

    Drawing of apparatus Safety During the course of the experiment it is imperative that the following safety checks are carried out. 1. 2. Standard laboratory safety rules must be observed. 3. Take care when working with mains voltage - equipment (laptops etc..)

  2. Describe how the properties of water are related to its roles in living organisms ...

    This also means that, compared with air, water releases heat energy slowly when situations cause it to cool. Water's high specific heat helps organisms to regulate their body temperatures more effectively.

  1. The Biological Importance of Water as a Solvent and as a Medium for Living ...

    Water is at its most dense at 4oC which is when its bonds are closest together. When water freezes the lattice arrangement of its structure move apart slightly and it floats on the surface. This means that the layer of ice insulates the water below which stays at 4oC and aquatic life can continue.

  2. Describe the Critical Role That Water Plays In Maintaining Life on Earth, Both as ...

    All living things need continuing supplies of water to survive. A plant needs water to keep up the internal pressure or turgidity in its cells and tissues (which maintains the plant's shape), to bring in dissolved minerals and raw materials from the soil, and for photosynthesis.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work